The invention relates to a clamping device with a clamping rail guided for displacement in its longitudinal direction and an actuating device which comprises a gripping element, by means of which the clamping rail can be displaced.
It is known from DE 299 08 240 U1 to arrange a clamping bar with a stationary counterstop so as to be pivotable on a housing of the actuating device in such a clamping device.
It is known from U.S. Pat. No. 4,989,847 to provide a detachable contact bar.
Proceeding from this state of the art, the object underlying the invention is to provide a clamping device which is simple to operate.
This object is accomplished in accordance with the invention, in a clamping device of the type described at the outset, in that a first contact element and a second contact element are held on the clamping rail, that the clamping rail is displaceable in relation to the first contact element and that the first contact element is rotatable relative to the actuating device.
As a result of the inventive clamping device, the contact elements seated on the clamping rail may also be aligned in relation to a workpiece during any one-handed operation without the actuating device needing to be turned or grasped. In addition, a contact element may be turned unlimitedly since no parts of the housing are in the way. As a result of the non-displaceability of the first contact element, a contact surface may, on the one hand, be made available for the clamping of a workpiece (this may also take place, in principle, by means of a contact surface of the actuating device itself), wherein, on the one hand, the rotatability of this contact element, the adjustment of a certain distance between the first contact element and the second contact element and a rotatability, which does not alter the relative alignment of the two contact elements during the rotation of the clamping rail, can be achieved in a simple manner with respect to production techniques.
In principle, the rotatability of the first contact element may be brought about in that this can be rotated against the clamping rail and/or the clamping rail can be rotated with the first contact element.
In the case of an embodiment which is simple from a constructional point of view and advantageous from the point of view of production techniques, the clamping rail is guided so as to be non-rotatably displaceable. The first contact element is then rotatable relative to the clamping rail. In particular, the second contact element is then designed to be rotationally symmetric transversely to the clamping rail. When the first contact element is turned, the relative orientation between the first and the second contact element is, nevertheless, not altered.
In a particularly advantageous embodiment, the clamping rail is mounted for rotation on the actuating device, wherein first and second contact elements are rotatable with the clamping rail. As a result, a set relative orientation of the contact elements transversely to the clamping rail is also maintained during rotation relative to the actuating device.
Advantageously, the clamping rail is unlimitedly rotatable with the contact elements held on it in order to obtain manifold possibilities for use.
It is particularly favorable from a constructional point of view when the clamping rail is guided for displacement by at least one bearing element. As a result, the displaceability of the clamping rail is ensured. The clamping rail is, in particular, guided for sliding displacement by the bearing element.
It is particularly advantageous when the bearing element itself is mounted for rotation on the actuating device in order to also ensure the rotatability of the clamping rail in this way.
For this purpose, a bearing element favorably guides the clamping rail so as to be non-rotatable and slidingly displaceable, i.e., the clamping rail is not rotatable relative to the bearing element and the rotation of the clamping rail is brought about via the rotation of the bearing element. It is then advantageous when the clamping rail has a profile which is designed such that the rotatability of the clamping rail can be blocked in relation to a bearing element, by means of which the clamping rail is guided for displacement.
In an advantageous embodiment it is provided for the clamping rail to have a flat profile, for example, a rectangular profile. Such a clamping rail may be produced inexpensively and during operational use is less susceptible to damage which could interfere with the sliding displaceability.
In an alternative embodiment which is, in particular, simple to produce, a bearing element guides the clamping rail so as to be rotatable and slidingly displaceable, i.e., such a bearing element is designed as a rotary slide bearing.
It is particularly favorable from the point of view of production techniques when at least one bearing element is designed as a deep-groove bearing which is arranged on the actuating device so as to be non-displaceable and rotatable by means of a groove. Such a deep-groove bearing may be produced in an inexpensive manner and also assembly of an inventive device is possible in a simple manner since only one such deep-groove bearing need be used and no additional securing means, such as screws, are necessary.
Furthermore, it is favorable from a constructional point of view when the first contact element is held on the housing of the actuating device via a deep-groove bearing so as to be non-displaceable and rotatable with the clamping rail. For example, the first contact element may be connected to the deep-groove bearing in one piece or in a form-locking manner. As a result, a slidingly displaceable mounting of the clamping rail is achieved, on the one hand, and, on the other hand, a rotary mounting. Furthermore, it is possible for the first contact element to be turned with the clamping rail and, therefore, its orientation in relation to the second contact element is also maintained during the rotation. In addition, the first contact element is held, as a result, on the housing of the actuating device so as to be non-displaceable so that the distance between the first contact element and the second contact element is altered during a displacement of the clamping rail in a constructionally simple manner.
The inventive clamping device may be operated in a simple manner when the gripping element comprises a handle arranged on the actuating device so as to be pivotable. In this respect, a respective handle can be present, in particular, for each direction of movement of the clamping rail or also only one single handle.
It is particularly favorable from a constructional point of view when at least one advancing element is provided which is arranged and designed such that it can be tilted contrary to the direction of displacement of the clamping rail in order to block the displaceability of the clamping rail in relation to the advancing element and that it is movable in the direction of displacement of the clamping rail. As a result, the clamping rail can be advanced in one direction in a simple manner during the actuation of the gripping element. An advancing element is advantageously arranged in the housing of the actuating device so as to be rotatable in order to ensure the rotatability of the clamping rail.
An advancing element is favorably tiltable and movable via a force acting on it by way of the gripping element.
When a pressure spring is arranged between an advancing element and a blocking element or holding element for exerting a restoring force on the advancing element contrary to the direction of displacement, the advancing element may be pushed back in a simple manner into its initial position, from which a further advancing of the clamping rail can be actuated.
In this respect, the blocking element is favorably arranged on a housing of the actuating device so as to be rotatable in order to bring about a rotary guidance of the clamping rail in this manner which is to a great extent free from play.
The blocking element or the holding element can favorably be brought into a blocking position, in which a displaceability of the clamping rail is blocked in one direction. This blocking element ensures that the clamping rail can be displaced only in a desired direction of advance whereas the displacement in the opposite direction is blocked. As a result, good clamping results can be obtained since the force acting on a workpiece, which is transferred due to the displacement of the clamping rail, is effective only in one direction.
A great ease of operation is achieved when a holding element is provided, by means of which the displaceability of the clamping rail can be blocked in one direction. Such a holding element, by means of which a blocking element can be held in a non-blocking position, is associated, in particular, with the blocking element. The blocking position may be set or discontinued (i.e. the non-blocking position may be set) in a simple manner via the holding element which may be moved, in particular, from outside the housing of the actuating device.
In this respect, the holding element can favorably be actuated independently of the gripping element so that the one-handed operability, in particular, is maintained.
The holding element is advantageously arranged on the actuating device so as to be non-rotatable in order, on the one hand, not to hinder the rotatability of the clamping rail and, on the other hand, to fulfill its holding function.
The holding element can favorably be fixed in a holding position, wherein a blocking element which is possibly provided is in a non-blocking position in the holding position. This prevents any jamming of the blocking element with the clamping rail and ensures in this way the displaceability of the clamping rail in the desired direction. In this respect, it is particularly advantageous when the holding element can be fixed in a holding position, in which the holding element is aligned essentially at right angles to the clamping rail. The sliding displaceability of the clamping rail is not hindered in such a right-angled position.
The holding element may be fixed in its holding position by means of a coupling pin in a simple manner from a constructional point of view and from the point of view of production techniques.
A contact surface for an advancing element, which limits the displaceability of an advancing element in the direction opposite to the direction of displacement of the clamping rail, is favorably formed in a housing of the actuating device. As a result, it is ensured that the advancing element is always pushed back into its initial position and can be brought into a position, in which it does not hinder the displacement of the clamping rail.
It is particularly advantageous when the actuating device is designed to be essentially in mirror symmetry to a central plane transversely to the direction of displacement of the clamping rail. As a result, it is possible in a simple way for the clamping rail to be displaceable in two opposite directions and, therefore, to be usable, in particular, as a clamping element and as a spreading element.
In this respect, a displacement of the first and the second contact elements towards one another and away from one another can favorably be actuated via the gripping element. As a result, a great ease of operation is made available since not only a clamping tool but also a spreading tool can be actuated via a one-handed operation.
A first advancing element is favorably provided for the displacement of the clamping rail in a first direction of displacement and a second advancing element for the displacement in an opposite direction. The displacement mechanism may then be essentially of the same design, irrespective of the direction of displacement, whereby the constructional expenditure is reduced.
It is particularly advantageous when first and second advancing elements can be tilted in opposite directions. As a result, a displacement of the clamping rail may be brought about, in particular, via gripping levers which can be pivoted in opposite directions.
In this respect, a first gripping lever of the gripping element favorably engages on the first advancing element and a second gripping lever on the second advancing element. As a result, the clamping rail may be displaced in the desired direction of displacement by an operator in a simple manner with great ease of operation.
It is particularly favorable from a constructional point of view when the first and second gripping levers can be pivoted in opposite directions for engagement on the associated advancing elements.
In an alternative embodiment, a gripping lever is provided, by means of which the first advancing element or the second advancing element may be displaced depending on the direction of pivoting.
It is particularly favorable from a constructional point of view when a first pressure spring, a first holding element and, optionally, a first blocking element are associated with the first advancing element and a second pressure spring, a second holding element and, optionally, a second blocking element are associated with the second advancing element.
It is particularly favorable when the first and second holding elements can be coupled to one another such that when the first blocking element is in a blocking position the second blocking element is in a non-blocking position and vice versa. As a result, it is possible in a constructionally simple manner for the clamping rail to be displaceable each time only in one direction whereas the displacement in the opposite direction is blocked. As a result, it is possible for the displacement of the clamping rail to be a pure xe2x80x9cclamping displacementxe2x80x9d or a pure xe2x80x9cspreading displacementxe2x80x9d, with which a force can be exerted on a workpiece in one direction (either clamping direction or spreading direction).
In this respect, a coupling device is favorably provided which can be secured on the actuating device in a first position, in which the first blocking element is fixed in a non-blocking position via the associated, first holding element and the second blocking element is in a blocking position, and can be secured in a second position, in which the first blocking element is in a blocking position and the second blocking element is fixed in a non-blocking position via the associated, second holding element. The direction of displacement of the clamping rail may be changed over as a result of the coupling device which can be arranged, for example, in the housing as a slidable element or can be a separate push-on element.
In its blocking position, the first blocking element is favorably tilted in a direction opposite to the second advancing element during its displacement and, accordingly, the second blocking element is tilted in a direction opposite to the first advancing element during its displacement. Such a tilting of the blocking element in a direction opposite to the associated advancing element facilitates a displacement of the advancing element itself since the displacement, with which the clamping rail is displaced as well, acts contrary to the tilting of the blocking element and, therefore, its blocking position is cancelled out for the displacement in the direction of displacement of the clamping rail. The clamping rail is, however, not displaceable in the opposite direction due to this tilting since the blocking is effective in this direction.
Favorably, the second advancing element is secured against tilting in the first position of the coupling device and the first advancing element is secured against tilting in the second position. As a result, the adjustment and changing over of the direction of displacement are possible in a simple manner.
The inventive clamping device may be produced in an inexpensive manner when the housing of the actuating device is designed and provided with recesses such that the movable parts are fixed in relation to the housing solely via the recesses acting as contact surfaces. No screw connections or the like are then necessary but rather the parts are held solely via the recesses so that the clamping device can, in particular, be assembled quickly and easily.
The housing also protects the movement mechanism for the displacement of the clamping rail and grease or oil for increasing the smooth operation is not removed from the movable parts during the operative use.
It is particularly favorable when the housing of the actuating device comprises a first housing section and a second housing section which can be fixed to one another. The structural parts can then be inserted into the first housing section, whereupon the second housing section is then fixed to the first housing section. As a result, the corresponding parts are secured in the housing. The fixing of the two housing parts may be brought about in a simple manner, for example, via screw connections.
It may be provided for the first contact element and/or the second contact element to be designed as a contact bar or also as a contact disk.
A contact element favorably has contact surfaces which are essentially of the same design transversely to the longitudinal direction of the clamping rail. As a result, such a contact element can be used not only for clamping a workpiece on a contact surface but also for spreading it at the other contact surface. In addition, the first contact element and the second contact element favorably have contact surfaces which are essentially of the same design, whereby the ease of operation is increased since a simple use in relation to clamping and spreading is, in particular, made possible.
In one embodiment which allows a high variability of use, the first contact element and/or second contact element are rotatable in relation to the clamping rail, for example, in that such a contact element is rotatable in a rotary bearing which is seated non-rotatably on the clamping rail. As a result, the contact elements can, on the one hand, be turned with the clamping rail, wherein their relative orientation is maintained and, on the other hand, the relative orientation may be adjusted.
In a further embodiment, a coupling element is provided, by means of which the first contact element and the second contact element can be coupled to one another such that they are turned with the clamping rail during rotation thereof. It is then sufficient to secure one contact element non-rotatably on the clamping rail. The other contact element is taken along during rotation of the clamping rail via the coupling element.
A rotatability of a contact element relative to the clamping rail may be achieved in a simple manner in that the contact element is seated on the clamping rail by means of a rotary bearing.
The following description of preferred embodiments of the invention serves to explain the invention in greater detail in conjunction with the drawings.